Grading machine

ABSTRACT

An improved diameter grading machine having a plurality of aligned pairs of rails, each pair forming a diverging slot therebetween from one end to the other for passage of articles therethrough. Articles of smallest minimum diameter fall through the slot nearest the end at which the articles are fed to the rails and larger diameter articles fall through the slot along the length of the rails according to their minimum diameter. One rail in each pair is mounted on a fixed support and the other rail of the pair is mounted on a support which is laterally adjustable with respect to the fixed support to adjust the slot width so that the rails can be simultaneously adjusted to grade items of different mean diameter with a minimum of adjustment. An improved feeding device singulates the articles for feeding to each of the rails. The feeding device has a plurality of spaced grooves of increasing width and depth juxtaposed with a plurality of ridges of increasing height and width.

United States Patent Chapman [54] GRADING MACHINE [72] Inventor: Robert R. Chapman, Lowell, Mich.

[731 Assignee: Sortex Company of North America,

Inc., Lowell, Mich.

[221 Filed: March 8, 1971 [21] Appl. No; 121,892

[52 us. c1. ..209/99 51 1111.01 ..B07c 5/04 [58] Field of Search ..209/98, 99, 107; 198/59, 60

[56] References Cited UNITED STATES PATENTS 2,908,389 10/1959 Lauer ..209/99 3,220,548 11/1965 Flodin ..209/107 Primary Examiner-Allen N. Knowles Assistant Examiner-Gene A. Church Attorney-John E. McGarry [451 Oct. 31, 1972 [5 7] ABSTRACT An improved diameter grading machine having a plu- I rality of aligned'pairs of rails, each pair forming a diverging slot therebetween from one end to the other for passage of articles therethrough. Articles of smallest minimum diameter fall through the slot nearest the end at which the articles are fed to the rails and larger diameter articles fall through the slot along the length of the rails according to their minimum diameter. One rail in each pair is mounted on a fixed support and the other rail of the pair is mounted on a supvport which is laterally adjustable with respect to the fixed support to adjust the slot width so that the rails can be simultaneously adjusted to grade items of different mean diameter with a minimum of adjustment. An improved feeding device singulates the articles for feeding to each of the rails. The feeding device has a plurality of spaced grooves of increasing width and depth juxtaposed with a plurality of ridges of increasing height and'width.

13 Claims, 7 Drawing Figures PAIE'NTEDMIBIM 3.701.418

SHEET 3 BF 3 IINVENTOR. ROBERT R. CHAPMAN 1 4/ ms ATTORHEI GRADING MACHINE BACKGROUND OF THE INVENTION 1 Field Of The Invention This invention relates to grading machines. In one of I its aspects the invention relates to a diameter grading machine having means for simultaneously adjusting the slot width between a plurality of grading rails. In another of its aspects, the invention relates to a grading machine with an improved singulating feeder tray.

2. State Of The Prior Art Articles such as peanuts, beans, rice, and pharmaceutical products, have a minimum and maximum diameter. These food items are frequently graded for sale of a more standard product. Pharmaceutical productsare graded'to sort misformed capsules-both undersized and oversized-from properly formed capsules. Machines have heretofore been developed for grading a single product and such machines are not readily adaptable for different products. In the case of pharmaceutical products, it has been impossible to readily switch from grading one type of capsule to another without loss of grading efficiency.

One commercially available diameter grading machine has a plurality of pairs of aligned rails. Each rail is mounted on a fixed support. One of the rails is adjustable on the support with respect to the other to change the width of the slot between the rails. However, each rail has to be adjusted separately at a plurality of spots along the rail, and a gauge has to be employed to make certain that each pair of rails has the same gap between them. Such adjustments are time consuming and tedious.

ln grading machines such as described above, it is necessary that the articles are fed seriatim to each pair of rails. If the articles are stacked on top of each other, for example, a smaller article might ride down along the rail to a point father than it should and fall into an area of larger diameter articles. Prior feeding devices have used a plurality of juxtaposed grooves of increasing width and depth for singulating the articles. Ocassionally, with the use of these feeding devices, articles are stacked on top of another as they are fed to the sorting rails. This results in a lower sorting efficiency than desirable.

OBJECTS By various aspects of this invention, one or more of the following, or other, objects can be obtained.

It is an object of this invention to provide an improved diameter sorting apparatus having a plurality of pairs of elongated rails forming a diverging slot through which articles pass according to their diameter, wherein the width of the slot between each pair of rails is simultaneously adjustable so that the grading device can be quickly converted from grading articles of one given average diameter to grading articles of a second given average diameter.

It is another object of this invention to provide a grading device having an improved feeding mechanism for singulating articles and feeding said articles seriatim to the grading device.

Other aspects, objects, and the several advantages of this invention are apparent to one skilled in the art from a study of this disclosure, the drawings, and the appended claims. i r

2 BRIEF STATEMENT OF THE INVENTION A size grading apparatus of the type in which articles are separated according to a minimum diameter has a plurality of pairs of aligned rails, each pair of the rails defining an opening or slot of a width increasing between one end and the other. The articles to be graded are fed to the one end of the rails and are moved along the rails until the width of the opening between the rails is greater than the minimum diameter of the articles. A plurality of bins'or other collection devices are provided beneath the rails to catch the articles as they fall through the rails.

Each pair of rails has a first rail member which is mounted on a first support member and a second rail member which is mounted on a second support member. The first support member is mounted for movement transverse to the rails with respect to the second support member so that the first rail member can be simultaneously adjusted with respect to the second rail member, thereby simultaneously changing the width of the opening between each pair of rails. In this manner, the machine is easily converted from sorting articles of one main diameter to sorting articles of another main diameter.

The articles which are graded by the machine are singulated and fed seriatim to each pair of rails. The feed ing means comprises a tray having a feeding end suspended above and overlapping one end of the rails. A plurality of spaced grooves in the feeding end of the tray increases in depth and in width in a direction toward the outer edge of the feeding end of the tray. Each of the grooves is positioned for discharging articles between a pair of rails. A plurality of spaced ridges is juxtaposed to the grooves for forcing the articles in the feeding end of the tray into the grooves. The ridges increase in height and thickness in a direction toward the outer edge of the feeding end of the tray.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a grading machine according to the invention;

FIG. 2 is a plan view of the grading machine;

FIG. 3 is a partial front elevational view of the grading machine;

FIG. 4 is a partial sectional view along lines 44 of FIG. 2;

FIG. 5 is a partial sectional FIG. 2;

FIG. 6 is a partial sectionalview along lines 6-6 of FIG. 2; and

FIG. 7 is a partial sectional view along lines 7-7 of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, there is shown a grading machine comprising a feed hopper 12 having a distribution tray 14 for singulating articles dispensed by the feed hopper and feeding said articles seriatim to sorting rails 16. The articles move along the sorting rails 16 and fall through the sorting rails according to their diameter into collection chutes I8, 20, and 22.

view along lines 5--5 of The feed hopper 12 is supported above the distribution tray by an upright frame member 21. The feed hopper 12 has openings 24 and 26 at the bottom portion thereof to dispense the articles into the distribution tray 14. The openings 24 and 26 may be adjustable so that the rate of dispensing of the articles from the feed hopper 12 equals the rate of sorting by the sorting rails 16.

The distribution tray 14 has an upwardly sloping floor 30 which joins a plurality of singulating feeders 32 for feeding the articles seriatim to the sorting rails. The singulating feeders 32 are formed from a plurality of grooves 34 increasingin width and depth from the top of the floor 30 to the feeding end of the tray. Triangular floor portions 36 and ridges 38 are juxtaposed to the spaced grooves along the edge of the distribution tray. The ridges 38 increase in height and width from the top edge of the sloping floor 30 to the feeding end of the tray.

A feeder deck 40 has an enlarged rear portion 42 (FIG. 4) with a plurality of elongated openings 43 (FIG. to permit passage of the articles therethrough. The distribution tray 14 is supported on the enlarged rear portion 42 of the feeder deck through spacers 44 and screws 46.

A blade spring 48 (FIG. 4) is secured to one end of the feeder deck 40 through fasteners 50. The feeder deck 40 is supported at the other end by another blade spring 52 (FIG. 3) and fasteners 54. Vibrational movement is imparted to the blade spring 48 through a conventional vibration means such as electromagnets (not shown). Suitable vibration means are described in Fraenkel, US. Pat. No. 3,002,617.

The sorting rails are best illustrated in FIG. 5. A fixed rail deck 56 is rigidly mounted on the feeder deck 40 through suitable fasteners (not shown). A plurality of elongated openings 58 in fixed rail deck 56 are in substantial registry with the openings 43 in the feeder deck 40. A guide strip 60 (FIGS. 2 and 6) of Nylon or other low friction material is secured to the outer end of the fixed rail deck 56 through fasteners 62. Fixed rails 66 are secured to the deck 56 and have a slanted outer guide portion 68 and a basev flange 70. A machine screw 72 extends through the base flange and threadably engages the fixed rail deck 56 to secure the fixed rail 66 to the fixed rail deck 56.

A movable rail deck 74 is mounted on top of fixed rail deck 46 and has elongated openings 76 in substantial registry with the elongated openings 58 and 43. One end of the rail deck 74 abuts the guide strip 50. The opposite end of the rail deck 74 abuts a thickened edge 59 of the fixed rail deck 56. The movable rail deck is thus mounted for movement transverse to the elongated openings 43, 58, and 76. Slots 78 (FIG. 5 and FIG. 2) are formed in the outer portions of the movable rail deck 74. Fasteners 80 having washers 82 extend through the slots 78 and releasably secure the movable rail deck 74 in a fixed position with respect to the fixed rail deck 56.

Movable rails 84 are fixed to the movable rail deck 74 through machine screws 96 which threadably engage the movable rail deck 74. The movable rails 84 have an overlying top portion 86 with an aperture 92 in vertical registry with the machine screw 72. Slanting side wall portions 88 of the movable rails 84 have an aperture 94 in vertical registry with the machine screw 96 which extends through a reverse bottom flange of movable rail 84. Machine screws 96 are tightened or adjusted by extending a screw driver through aperture 94. Similarly, machine screw 72 is tightened or loosened by extending a screw driver through aperture 92.

An actuator for moving the movable rail deck 74 with respect to the fixed rail deck 56 is illustrated in FIGS. 2 and 7 to which reference is now made. The movable rail deck 74 has a circular opening 98. A shaft 100 has a threaded bottom portion 102 which threadably engages a tapped hole 104 in the fixed rail deck 56. A circular plate 106 is eccentrically mounted on the shaft 100. A handle 108 is provided on the shaft 100 for rotating the shaft, including the plate 106, with respect to the movable rail deck 74. As seen in FIG. 2, a scale 110, mounted on the fixed rail deck 56, forms a gauge with the edge of the movable rail deck 74.

The rails 66 and 84 form an elongated slot in substantial vertical registry with the elongated openings 43, 58, and 76. The width of the slot increases from the feeding end of the rails, adjacent the feeders 32, to the opposite end thereof. The taper of the slot is set by placing rail 66 at a slight angle with respect to opening 76 and rail 84. Alternately, the guide portion 68 of rail 66 and/or the side portion 88 of rail 84 can be tapered to make the tapered slot. Articles 112 ride between the rails until their diameter is less than the width of the slot.

The rails 66 and 84 are formed out of a thin metal and are somewhat flexible. The articles are thus not easily caught between the rails.

OPERATION In operation, the fixed rails 66 are mounted so that the slot between the fixed rail 66 and the movable rail 86 increases between the feeding edge of the rails and the opposite end. The articles to be sorted are fed into the feed hopper l2 and pass into the distribution tray 14 through the openings 24 and 26 in the feed hopper. Vibration is imparted to the distribution tray 14 and the sorting rails 16 through electromagnets (not shown) or other suitable vibration producing means. The articles move along the distribution tray, up sloping floor 30 and into the grooves 34. As the articles move to the outer edge of the distribution tray, they will fall into the grooves 34. Articles in triangular floor portion 36 are forced into the grooves 36 by the ridges. Articles on the ridges 38 fall to one side or the other and end up in grooves 34. The ridges 38 tend to force the articles into the grooves at the earliest possible moment, thereby avoiding depositing of one article on top of the other at the end of the grooves.

The articles are thus fed seriatim from each of the grooves 34 into the sorting rails between the fixed rail 66 and the movable rail 88. The articles 112 will thus be supported between the slanted guide portion 68 of the fixed rail and the slanted side portion 88 of. the movable rail 84 as seen in FIG. 5. The articles are moved along the sorting rails (i.e., from right to left in FIG. 2) by the vibratory movement of the feeder deck and the rails. As disclosed above, the gap between the rails increases from the feeding end to the opposite end of the rails. Thus, at some point along the rails, the slot 22. The articles with the smallest minimum diameter will drop through the rails first. The articles with larger minimum diameters will be moved down the rails and will drop through the articles at a later point. Thus, those articles which fall into chute 18 will be smaller than the articles falling into chutes 20 and 22. Conversely, those articles falling into chute 22 will be larger than the articles in chutes l8 and 20. As many collection chutes can be provided as are desirable, depending on the nature of the operation.

It may be desirable to grade different kinds of products which have dilferent mean diameters. If so, the setting of the slot between rails may not be suitable for the two different products. For example, if the second product has a much smaller mean diameter than the first product, substantially all of the product would fall through the rails near the feeding end and there would be essentially no sorting of the product. According to the invention, the slot between each pair of rails is simultaneously adjustable so that the width of the slot between the rails is rapidly and accurately changed. The slot width is changed by loosening each of the fasteners 80 so that the movable rail deck 74 can slide in a direction transverse to the rails with respect to the fixed rail deck 56. The handle 108 is then rotated, in a counterclockwise direction for example as viewed from FIG. 2, so that the movable rail deck 74 moves to the right with respect to the fixed rail deck 56 as viewed from FIG. 5. When this occurs, the width of the slot at any given point between each of the pairs of rails will simultaneously be decreased. The extent of the movement can be visually gauged by observing the scale 110. When the desired adjustment has been made, the fasteners 80 are then tightened to secure the movable rail deck 74 in a fixed position with respect to the fixed rail deck 56. The different product can then be fed into the feed hopper 12, the vibrator started, and the product will be graded.

It is obvious from the foregoing disclosure that the inventive grading machine has an improved feeding device for singulating the feed to grading rails and a means for quickly, easily and simultaneously adjusting the gap between each pair of rails.

Reasonable variation and modification are possible within the scope of the foregoing disclosure, the drawings, and the appended claims without departing from the spirit of the invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as fol lows.

1. A size grading machine of the type in which articles are separated according to a minimum diameter, said machine comprising: I

a plurality of pairs of aligned rails, each pair of said rails defining an opening of increasing width between one end of said rails and the other;

means beneath said rails for gathering articles passing through said openings between said rails at different intervals therealong to collect articles having different minimum diameters;

cle will be channelled into collection chutes 18, 20, or

means for feeding said articles seriatim to said one end of each of said pairs of rails;

means for moving said articles along each of said pairs of rails from said one end to the other;

the improvement which comprises:

first and second support members; each of said pairs of rails having a first rail member rigidly mounted on said first support member for rigid uniform movement therewith, and a second rail member rigidly mounted on said second support member;

means mounting said first support member for movement transverse to said rails with respect to said second support member;

whereby each of said first :rail members can be simultaneously and uniformly adjusted with respect to said second rail members so that said opening between each pair of said rails can be uniformly adjusted for sorting articles of different average diameter; and

means for fixing said first support member with respect to said second support member in various adjusted positions.

2. A size grading apparatus according to claim 1 wherein said feeding means comprises a tray having a feeding end suspended above and overlapping said one end of said rails, a plurality of spaced grooves in said feeding end of said tray, each of said grooves increasing in depth and width in a direction toward the outer edge of said feeding end of said tray, each of said grooves being positioned above a separate pair of said rails for discharging said articles in said grooves into said rails; and

a plurality of spaced ridges juxtaposed to said grooves for forcing said articles in said feeding end of said tray into said grooves.

3. A size grading apparatus according to claim 2 wherein said ridges increase in height and thickness in a direction toward said outer edge of said feeding end of said tray.

4. A size grading apparatus according to claim 2 and further including vibratory means for moving said articles along said tray to said outer edge of said feeding end.

5. A size grading apparatus according to claim 1 wherein said moving means includes a means for vibrating said rails along their longitudinal axis.

6. A size grading apparatus according to claim 1 wherein each of said first and second rail members have side walls which slope downwardly toward said opening therebetween, and each of said rail members is rigidly secured to its respective support member.

7. A size grading apparatus according to claim 6 wherein said second support member comprises a fixed plate having a plurality of elongated openings, said plate being positioned beneath said rails; and said first support member comprising a plate having a plurality of elongated openings, said first support member being positioned on top of said second support member with the elongated openings of each of said plates being in substantial vertical registry.

8. A size grading apparatus according to claim 7 and further comprising means for actuating adjusting movement of said first plate with respect to said second plate.

9. A size grading apparatus comprising:

a plurality of aligned elongated article receiving means, each of said article receiving means including means for separating said articles according to one of its dimensions;

V means for moving said articles from one end of said article receiving means to the other, thereby effecting a separation of said articles accordingto said one dimension thereof; and

means for feeding said articles seriatim to said one end of said article receiving means;

the improvement in said aiticle feeding means comprising:

a tray having a feeding end suspended above and overlapping said ,one end of said article receiving means;

a plurality of spaced grooves in said feeding end of said tray, each of said grooves increasing in depth and width toward the outer edge of said feeding end of said tray; each of said grooves terminating at said outer edge above a separate article receiving means for discharging said articles into said receiving means; and

a plurality of spaced ridges juxtaposed to said grooves for forcing said articles in said feeding end of said tray into said grooves.

10. A size grading apparatus according to claim 9 wherein said ridges increase in height and thickness in a direction toward said outer edge of said feeder tray.

11. A size grading apparatus according to claim 10 wherein one of said ridges extends substantially between each pair of adjacent grooves at said outer edge of said feeder tray.

12. A size grading apparatus according to claim 9 and further comprising means to vibrate said tray to move said articles in a direction toward said outer edge of said feeder end.

13. A size grading apparatus according to claim 9 wherein said tray has a floor portion adjacent said feeder end which floor portion slopes upwardly toward said feeder end of said tray. 

1. A size grading machine of the type in which articles are separated according to a minimum diameter, said machine comprising: a plurality of pairs of aligned rails, each pair of said rails defining an opening of increasing width between one end of said rails and the other; means beneath said rails for gathering articles passing through said openings between said rails at different intervals therealong to collect articles having different minimum diameters; means for feeding said articles seriatim to said one end of each of said pairs of rails; means for moving said articles along each of said pairs of rails from said one end to the other; the improvement which comprises: first and second support members; each of said pairs of rails having a first rail member rigidly mounted on said first support member for rigid uniform movement therewith, and a second rail member rigidly mounted on said second support member; means mounting said first support member for movement transverse to said rails with respect to said second support member; whereby each of said first rail members can be simultaneously and uniformly adjusted with respect to said second rail members so that said opening between each pair of said rails can be uniformly adjusted for sorting articles of different average diameter; and means for fixing said first support member with respect to said second support member in various adjusted positions.
 2. A size grading apparatus according to claim 1 wherein said feeding means comprises a tray having a feeding end suspended above and overlapping said one end of said rails, a plurality of spaced grooves in said feeding end of said tray, each of said grooves increasing in depth and width in a direction toward the outer edge of said feeding end of said tray, each of said grooves being positioned above a separate pair of said rails for discharging said articles in said grooves into said rails; and a plurality of spaced ridges juxtaposed to said grooves for forcing said articles in said feeding end of said tray into said grooves.
 3. A size grading apparatus according to claim 2 wherein said ridges increase in height and thickness in a direction toward said outer edge of said feeding end of said tray.
 4. A size grading apparatus according to claim 2 and further including vibratory means for moving said articles along said tray to said outer edge of said feeding end.
 5. A size grading apparatus according to claim 1 wherein said moving means includes a means for vibrating said rails along their longitudinal axis.
 6. A size grading apparatus according to claim 1 wherein each of said first and second rail members have side walls which slope downwardly toward said opening therebetween, and each of said rail members is rigidly secUred to its respective support member.
 7. A size grading apparatus according to claim 6 wherein said second support member comprises a fixed plate having a plurality of elongated openings, said plate being positioned beneath said rails; and said first support member comprising a plate having a plurality of elongated openings, said first support member being positioned on top of said second support member with the elongated openings of each of said plates being in substantial vertical registry.
 8. A size grading apparatus according to claim 7 and further comprising means for actuating adjusting movement of said first plate with respect to said second plate.
 9. A size grading apparatus comprising: a plurality of aligned elongated article receiving means, each of said article receiving means including means for separating said articles according to one of its dimensions; means for moving said articles from one end of said article receiving means to the other, thereby effecting a separation of said articles according to said one dimension thereof; and means for feeding said articles seriatim to said one end of said article receiving means; the improvement in said article feeding means comprising: a tray having a feeding end suspended above and overlapping said one end of said article receiving means; a plurality of spaced grooves in said feeding end of said tray, each of said grooves increasing in depth and width toward the outer edge of said feeding end of said tray, each of said grooves terminating at said outer edge above a separate article receiving means for discharging said articles into said receiving means; and a plurality of spaced ridges juxtaposed to said grooves for forcing said articles in said feeding end of said tray into said grooves.
 10. A size grading apparatus according to claim 9 wherein said ridges increase in height and thickness in a direction toward said outer edge of said feeder tray.
 11. A size grading apparatus according to claim 10 wherein one of said ridges extends substantially between each pair of adjacent grooves at said outer edge of said feeder tray.
 12. A size grading apparatus according to claim 9 and further comprising means to vibrate said tray to move said articles in a direction toward said outer edge of said feeding end.
 13. A size grading apparatus according to claim 9 wherein said tray has a floor portion adjacent said feeding end which floor portion slopes upwardly toward said feeding end of said tray. 